A profile emerging from a continuous-casting machine is normally cut into workpieces that are either rolled immediately, while still hot, or reheated and then rolled. The rolling equipment typically includes at least one universal mill having a vertically spaced pair of rollers rotatable about horizontal axes and a horizontally spaced pair of rollers rotatable about vertical axes. As a rule such roll trains are used reversing style, that is passing the workpiece in one direction through the stands, then back through in the opposite direction.
As is known (See SMS Schloemann-Siemag AG, Dusseldorf publication W No. 2/3115) the input end of a rolling train for rolling out continuously cast workpieces of this type has a heavy duty intake stage which is separated by a considerable distance from the following roll stands which are in turn spaced quite a bit upstream of the output-end finishing roll stands. Similarly German patent document No. 3,627,729 suggests doing away with one of these roll stands when the second or last of the universal stands of the reversing tandem group is set up as a finishing stand. By using a large number of passes through the rolling train it is possible to eliminate other stands provided the workpieces are a continuously cast strand and not a massive billet or bloom.
In such systems it has been found advantageous to use so-called dogbone-section workpieces (See pp 904 and 905 of The Making, Shaping, and Treating of Steel [1987; the Association of Iron and Steel Engineers]) as the starting profile workpiece. Such a workpiece section, which is what is used according to this invention, has been found to greatly facilitate the production of profiled finished products, in particular I-beams.
Thus starting with a dogbone-section workpiece it is possible using a reversing tandem roll train to produce I-beams, and using standard two-roll units channels or U-sections can be produced. Since, however, a change in profile demands the use of a new mold and substantial changeover time, it is necessary to shut down between runs of similar but differently dimensioned workpieces.